[PATCH v3] mtd: spi-nor: fix spansion quad enable

[Esponde, Joel]

> -----Message d'origine-----
> De : Marek Vasut [mailto:marek.vasut at gmail.com]
> Envoyé : vendredi 25 novembre 2016 16:08
> À : Cyrille Pitchen <cyrille.pitchen at atmel.com>; Esponde, Joel
> <Joel.Esponde at Honeywell.com>; linux-mtd at lists.infradead.org
> Objet : Re: [PATCH v3] mtd: spi-nor: fix spansion quad enable
> 
> On 11/25/2016 03:50 PM, Cyrille Pitchen wrote:
> > Hi Marek,
> 
> Hi,
> 
> > Le 25/11/2016 à 15:17, Marek Vasut a écrit :
> >> On 11/23/2016 12:47 PM, Joël Esponde wrote:
> >>> With the S25FL127S nor flash part, each writing to the configuration
> >>> register takes hundreds of ms. During that  time, no more accesses
> >>> to the flash should be done (even reads).
> >>>
> >>> This commit adds a wait loop after the register writing until the
> >>> flash finishes its work.
> >>>
> >>> This issue could make rootfs mounting fail when the latter was done
> >>> too much closely to this quad enable bit setting step. And in this
> >>> case, a driver as UBIFS may try to recover the filesystem and may
> >>> broke it completely.
> >>
> >> Does this apply to all spansion chips or only to selected few ?
> >>
> >
> > I've recently faced the very same issue with Winbond memories, which
> > use the same procedure as Spansion to set the Quad Enable bit.
> > More precisely, in my case it was some bare metal (bootloader) code
> > but the issue was the same, there was no polling of busy bit from the
> > Status Register after having set the QE bit in the Status Register 2 /
> > Control Register 1. Then the next SPI command came too early and
> > failed because the memory was actually still busy.
> >
> > I faced this issue with Winbond W25Q256 and W25M512.
> 
> So we can leave this code as is ?
> 


Hi,

I checked these data sheets, and in all of them, Bit 0 of the Status Register stands for WIP (Work in progress).

S25FL032P	http://www.cypress.com/file/196861/download#G4.1231516
S25FL064P	http://www.cypress.com/file/196856/download#G3.1231516
S25FL127S	http://www.cypress.com/file/177961/download#G3.1468489
S25FL128S,
S25FL256S	http://www.cypress.com/file/177966/download#G3.1254282
S25FL512S,
S70FL01GS	http://www.cypress.com/file/177971/download#G3.1238704
S25FL129P	http://www.cypress.com/file/197121/download#G4.1231516
S25FL004K,
S25FL008K,
S25FL016K	http://www.mouser.com/ds/2/380/spansion%20inc_s25fl004k-016k_00-329492.pdf#page=16&zoom=auto,61,683
S25FL128K	http://www.cypress.com/file/228376/download#G4.1299435
S25FL116K,
S25FL132K,
S25FL164K	http://www.cypress.com/file/196886/download#G3.1239521
S25FL204K	http://www.cypress.com/file/196871/download#G4.1354778

I was not able to find the data sheets of S25SL parts.
Based on this old patch provided by an Spansion engineer, it looks like S25SL family never existed:
https://patchwork.ozlabs.org/patch/59109/

Regards,

Joël